Qualys researchers have identified a critical vulnerability (CVE-2024-6387) in OpenSSH's server (sshd) that affects glibc-based Linux systems. This flaw could allow unauthenticated attackers to achieve remote code execution on potentially millions of targets, ultimately granting root-level access and potential system takeover. The bug, dubbed regreSSHion, is a regression of a previously patched vulnerability from 2006, reintroduced inadvertently in OpenSSH 8.5p1. Systems running glibc, particularly 32-bit architectures, are at risk. OpenBSD systems are the exception due to a security tweak implemented in 2001. Exploiting this flaw requires patience and multiple attempts due to a remote race condition nature. All OpenSSH versions prior to 4.4p1 are vulnerable, and versions from 8.5p1 to 9.8p1 need immediate patching. Qualys suggests limiting SSH access, network segmentation, and monitoring for exploit attempts to mitigate risks. Despite this flaw, OpenSSH is hailed for its robust security measures and design. Update your systems to the latest version to ensure protection against this potentially devastating vulnerability.